If I have a 2 foot fluorescent light with the tube rated at 21 W then 
what power rating would be the equivalent incandescent bulb?

The tube is straight and very approximately 1.25 inches im diameter

Is there a lookup table for comparing light output of fluorecent and 
incandescent bulbs?  (I can't find one with Google.)

Peter Davis wrote:

> If I have a 2 foot fluorescent light with the tube rated at 21 W then 
> what power rating would be the equivalent incandescent bulb?
> 
> The tube is straight and very approximately 1.25 inches im diameter
> 
> Is there a lookup table for comparing light output of fluorecent and 
> incandescent bulbs?  (I can't find one with Google.)


Can I suggest that you go to the manufacturer's web site?

Lumen output from different makes/models of the same size 
tube vary greatly - Osram has lamps which give 10% more 
lumens than a standard tube for the same wattage, or 8% more 
lumens for 15% less power and nearly twice the life 
expectancy. Also, lumen output for incandescent lamps also 
varies greatly between manufacturers and models. For 
example, Osram's Superlux Krypton gnerate 10% more lumens 
than their standard lamps, for the same input power.

-- 
Sue

Peter Davis wrote:

> If I have a 2 foot fluorescent light with the tube rated at 21 W then

> what power rating would be the equivalent incandescent bulb?
>
> The tube is straight and very approximately 1.25 inches im diameter
>
> Is there a lookup table for comparing light output of fluorecent and
> incandescent bulbs?  (I can't find one with Google.)


apx 75w.

Or if you put a nasty cool white tube in it, or a nice ££
triphosphor, you'll get a little bit more light.


NT

"Peter Davis"  wrote in message
news:965DB75F69B275D4AM2@204.153.244.156...

> If I have a 2 foot fluorescent light with the tube rated at 21 W then
> what power rating would be the equivalent incandescent bulb?
>
> The tube is straight and very approximately 1.25 inches im diameter
>
> Is there a lookup table for comparing light output of fluorecent and
> incandescent bulbs?  (I can't find one with Google.)


Linear fluorescent lamps are named according to diameter, in 1/8 's of an
inch.  T8 is (8/8) = 1" diameter, T12 is (12/8) = 1.5" diameter, etc.  I
don't hear of T10 much.  I would think you'd want a 100W or, likely, even
bigger incandescent to match the lumen output of a 20W fluorescent.  What is
the fluorescent fixture like (bare striplight?  clear wraparound acrylic
lens?  ?) and what fixture would you have in mind for the incandescent (bare
lamp?  recessed potlight?  ?).  It can make a big difference in terms of the
amount of the lumens that are delivered.

There are lighting newsgroups, if you find one of those you'll probably get
lots of answers.

j

bigcat@meeow.co.uk wrote:

> Peter Davis wrote:
> > If I have a 2 foot fluorescent light with the tube rated at 21 W
then
>
> > what power rating would be the equivalent incandescent bulb?
> >
> > The tube is straight and very approximately 1.25 inches im diameter
> >
> > Is there a lookup table for comparing light output of fluorecent
and
> > incandescent bulbs?  (I can't find one with Google.)
>
> apx 75w.
>
> Or if you put a nasty cool white tube in it, or a nice ££
> triphosphor, you'll get a little bit more light.



sci.eng.lighting if you want more detail

NT